We in the bucket teeth, sometimes sticky sand phenomenon, so how to prevent bucket tooth bonded sand?
1, compared with cast iron, cast steel casting temperature is higher, sometimes as high as 1560 - 1620 ℃, high casting temperature is mainly to prevent steel casting cold lap, but at the same time, such a high temperature thermal effect on the sand for long time, the cast big scouring force. Core sand in the back of the sand can not, because the return sand, fine sand, dust, iron sand too much, this will lead to sand sintering temperature is low, so the time to add new sand.
Compaction is not the problem .
2, sand mold casting sand sand stick, certainly not tight, in before casting must each piece of sand are tested, to enhance and ensure the casting compactness and compactness homogeneity. For difficult to compact and particularly tight corner. The sand compaction to high (usually ≥ 85) requirements, good uniformity, reduce sand gap, with particular attention to the core damage repair should be in place, not because of the existence of local osteoporosis repair.
3, attention should be paid to the gating system and riser, should avoid the casting and mould to produce local overheating. The design of gating system should avoid the ingate directly punching mould wall.
4, appropriate to reduce the pouring temperature, casting speed and pouring height, the so-called "reduced" mean in the premise that can cast into casting, reduce metal delta forces on sand and the physical and chemical effects. Note that reducing the pouring height, reducing the height and pouring cup height, to reduce the metal liquid dynamic pressure, static pressure and heat shock on the casting stress. The tooth casting, wall is not thick, but high casting temperature, increase heat time Steel Chau and cavity surface, pouring molten steel on the cavity of the dynamic pressure and static pressure, to create the conditions for the mechanical penetration.